Bills defense has two big holes to fill in 2014

The defense should be the strongest part of the 2014 Buffalo Bills but that doesn't mean there aren't key questions facing the unit as training camp approaches. The two biggest questions are the direct result of key off season losses in Defensive Cordinator Mike Pettine and safety Jairus Byrd.

Jim Schwartz takes over for Pettine and becomes the Bills 4th different coordinator in as many years. Schwartz, who oversaw successful defenses over an eight year run as a coordinator with Tennessee, will have some big shoes to fill.

In just one season, Pettine guided the Bills to an almost across the board improvement and installed one of the most entertaining defenses Bills fans have seen in a long time. From a statistical standpoint, the Bills improved in points allowed, total yards, rush yards, pass yards, takeaways, third down efficiency, completion percentage, red zone touchdown percentage and sacks. The 57 sacks recorded in 2013 was a franchise record.

Schwartz's biggest contribution could be improving the Bills run defense which went from historically bad to just bad last season. The Bills were 28th in NFL in rushing yards allowed per game and gave up 19 runs of 20 or more yards, the most by any defense in the league. The Titans were ranked in the top 10 in run defense in five of the eight years with Schwartz as their coordinator.

The Bills should have one of the best defensive lines in the NFL with Mario Williams, Kyle Williams, Marcell Dareus and Jerry Hughes. The main question up front is whether or not Dareus will be suspended by the NFL for his off field transgressions during the off season. The Alabama product had a break through season in 2013 with career highs in tackles(71) and sacks(7.5). Dareus now has 18.5 sacks in his first three years.

Speaking of sacks, Mario Williams has a bunch as well. 23.5 to be exact in his first two campaigns with Buffalo. Its the best sack total in back to back years since 2007 and 2008 when Aaron Schobel had 26. Williams, who was on the field for 87% of the defensive snaps last season, also had three forced fumbles, two fumble recoveries and seven passes defended while seeing time at both left and right end.

Hughes presents one of the more interesting questions for the upcoming season. The former first round draft pick of the Indianapolis Colts also had a break through year with a career best 10 sacks. This after recording only five sacks in three years with limited playing time for the Colts. Hughes will be an unrestricted free agent after the season and if he has another big year, he might price himself out of the Bills budget. You'd have to wonder whether or not the team would want to hand out a big contract to a pass rushing end that will probably be on the field about 50% of the time.

Linebacker Kiko Alonso took the NFL by storm as a rookie. The second round pick from Oregon was on the field for every single snap last season, almost 1100 total. He led the team in tackles(159) and was third in the NFL. Alonso added four interceptions, two sacks, two fumble recoveries and one forced fumble. Year number two will find Alonso moving to the outside where the team hopes he will take less of a beating as opposed to playing in the middle.

The new MLB is Brandon Spikes, signed away from New England in free agency. What impact will Spikes have? He should help solidify the iffy run defense but Spikes might be one and done with the Bills since he signed a one year contract.

The secondary has a huge hole to fill after the departure of Byrd who signed with New Orleans after the Bills opted not to use the franchise tag. Byrd flies south(I know its corny but I couldn't resist) along with 22 career interceptions, 33 passes defended and 11 forced fumbles in 73 games. Who steps in to fill the void? As far as the starting spot, the two most likely candidates are Da'Norris Searcy or Duke Williams. As far as the game changing plays, perhaps Aaron Williams can pick up some of the slack. A bust as a cornerback in 2011 and 2012, Williams was a revelation at safety in 2013. The former second round draft pick had four interceptions, 11 passes defended and a forced fumble in 14 games and earned himself a four year, $26 million contract extension.

Will this be the year Stephon Gilmore becomes a true shutdown corner? The former first round pick was easily the best cornerback in camp last year before suffering an injury. He missed the first six games of the season with a broken hand and struggled when he finally got back to the playing field while wearing a giant club. Gilmore has just three picks in his 27 career games.

Leodis McKelvin had his best year as a Bill last season and is the favorite to be the starter opposite Gilmore. Did McKlevin finally turn his game around or was last year a byproduct of the improved pass rush and confusion caused by Pettine's defenses and their disguises?

All the fun starts on July 20th at St. John Fisher college in Pittsford.